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Pronunciation: si


  1. The 23rd letter of the Greek alphabet (?).
  2. (?) Symbol for pseudouridine; pseudo-; wave function; the dihedral angle of rotation about the C1–Ca bond associated with a peptide bond.
  3. Pounds per square inch.

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.